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A Time Line of Emerging Zoonoses and Epidemics of the 21st Century A Global Perspective on the Epidemics of Foot-and-Mouth Disease, BSE, West Nile Encephalitis, SARS, Monkey Pox, and Avian Influenza. FMD. Avian Influenza. West Nile Virus Infections Human cases 2003… 9862 (~44% encephalitis)
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A Time Line of Emerging Zoonoses and Epidemics of the 21st CenturyA Global Perspective on the Epidemics of Foot-and-Mouth Disease, BSE, West Nile Encephalitis, SARS, Monkey Pox, and Avian Influenza. FMD Avian Influenza West Nile Virus Infections Human cases 2003… 9862 (~44% encephalitis) Human deaths 2003… 264 Human cases 2004… 2535 Human deaths 2004… 98 Equine deaths 1999-2004 15,000 Monkeypox
Bursting Bubbles of the 21st Century Clash of Civilizations Y2K Computer Crisis Right of Pre-emptive Action and War in Iraq Florida Hurricanes Bioterrorism Naturally Occurring Emerging Diseases and Epidemics With acknowledgement for the idea to Thomas Friedman New York Times April 24 2003
What are the Driving Forces of Epidemics? • Accelerated global trading patterns of the late 20th Century (brought about in part by democracy and major trading blocks) • Technical sophistication in food processing masking true origins • Exposure to new pathogens through ecosystem disruption (human population pressures) Major trading Blocks
Driving Forces of Epidemics contd. • Evolutionary pressures through overpopulation and change in tropism • Speed of transportation • Unique combination of factors that we truly do not understand (i.e. akin to the Hurricanes in Florida in 2004) We need to shift our focus from economy to ecology!
Speed of Global Travel in Relation to World Population Growth “No city on the earth is now more than 24 hours away from any other”. Economist 2003 “Annually, the world's airlines carry a staggering total approaching some two billion passengers. At any one moment, about half a million people world-wide are flying in commercial aircraft “ Select Committee on Science and Technology Fifth Report UK Parliament 2000
Recent Events Have Emphasized the Importance of Wildlife Species in Understanding the Epidemiology of Zoonoses West Nile Monkeypox SARS Avian Influenza
FMD Progress of an Epidemic What happened February 20 (first recognition in Essex) to April 11 (the turning point of the epidemic) and thereafter 21 cases Netherlands 2 cases in France 1 case in Ireland April 11 June 4 http://news.bbc.co.uk/hi/english/in_depth/uk/2001/foot_and_mouth/default.stm http://www.guardian.co.uk/footandmouth
Welfare : The Cost in Animals&The Psychological Trauma on Society But animals were also slaughtered on 7,549 premises because they were either Contiguous Premises/ Dangerous Contacts (7,294 ) or Slaughtered on Suspicion (255) September 30 Total outbreaks 2030 Slaughtered 3,940,000
Late Summer 2001The Future and FMDWhere will the road take us?
Bioterrorism emerges in the USA “If that hideousness (FMD) came here, it wouldn't be any more hideous for the animals -- they are all bound for a ghastly death anyway. But it would wake up consumers...I openly hope that it comes here. Smallpox Anthrax Oct 2001 Ingrid Newkirk President of People for the Ethical Treatment of Animals (PETA) Talking on FMD April 2001 Economist November 2002
Severe Acute Respiratory Syndrome SARS A new disease; a new virus! SARS map courtesy of WebMD
SARS Outbreak, Worldwide Cases by Country (June 3, 2003) Germany: 10 Sweden: 3 Finland: 1 Russian Federation: 1 Canada: 198 Romania: 1 United Kingdom: 4 Mongolia: 9 Ireland: 1 Rep. Of Korea: 3 France: 7 United States: 66 Spain: 1 China: 5,328 Taiwan: 684 Switzerland: 1 Hong Kong: 1,746 Italy: 9 India: 3 Macao: 1 Philippines: 12 Kuwait: 1 Vietnam: 63 Colombia: 1 Indonesia: 2 Thailand: 8 Singapore: 206 Brazil: 2 Malaysia: 5 Australia: 5 South Africa: 1 According to the World Health Organization (WHO), during the SARS outbreak of 2003, a total of 8,098 people worldwide became sick with SARS; of these, 774 died. New Zealand: 1
The first clues that SARS may be a zoonotic disease • Food handlers with likely animal contact were over represented in early cases (9/23, 39%) • People living near markets were over represented in early cases Video Masked Palm Civets Courtesy AP
12,500 Km 2000 Km Guangzhou 4900 Km 3200 Km The International Trade in Wildlife Slide Courtesy of Dr Billy KareshWildlife Conservation Organization
Did Smallpox hit the USA in May 2003? Fortunately not! It was Monkeypox. Dr Kurt Zaeske, DVM Wauwatosa, WI
WHO / AFIP Monkeypox in monkeys and humans in West and Central Africa Smallpox http://www.cdc.gov/ncidod/monkeypox/index.htm
WHO / AFIP Monkeypox and the reservoir host http://www.cdc.gov/ncidod/monkeypox/index.htm
Human cases (71) of monkeypox in USA 2003 by date of onset MMWR July 11, 2003 / 52(27);642-646
How did this happen? Prairie dogs
Movement of Imported African Rodents MMWR July 11, 2003 / 52(27);642-646 http://www.cdc.gov/mmwr/preview/mmwrhtml/mm5227a5.htm
Is there any precedent? Human, Cow and Cat Infections with Cowpox Virus in Europe Bank Vole Clethrionomys glareolus
Pandemic threat of human influenza Avian Influenza H5N1 in Asia“Enemy at the gate” With thanks to V. Martin, L. Sims, J. Lubroth, S. Kahn, J. Domenech, C. Benignoand Wantanee Kalpravidh of FAO
H5N1 Influenza virus in Poultry and Humans in Asia • New virus, which, if it mutates to easily infect humans, could infect entire human population. • If were to occur in the USA, 15-35% of the population might be affected, at a cost between $71 and $167 billion
The agricultural landscape of Vietnam is based on rice production
HA NA 8 7 6 5 4 3 2 1 Influenza AA promiscuous virus! • Orthomyxovirus • Envelope • Surface spikes • Hemagglutinin protein (HA) (16 types) • Neuraminidase protein (NA) (9 types) • SS(-) RNA • 8 segmented genes
The pig is the “Mixing Vessel” Why H5N1 is of particular concern Traditional belief of antigenic shift leading to pandemics of human influenza H5NI influenza is able to infect humans directly ?
DPRK H7 Philippines H5 Malaysia H5N1 Situation in July, but constantly changing! H5-affected countries with cases in the last 3 months H5-affected countries without cases in the last 3 months H7-affected countries H5-affected countries with reported human clinical cases/seropositive
Recent Spread of H5N1and the Questioned Role of Migratory Birds 17 August The East Asian- Australasian Flyway Bar-headed goose http://www.scz.org/animals/g/bhgoose2.html http://www.tasweb.com.au/awsg/eafw.htm
History and Evolution of H5N1 HPAI viruses Key epidemiological findings • Nomadic or free-range ducks • Contact wild waterbirds • Virus shedding and spreading • Reservoir of infection • Live bird markets • Cultural practices
Conclusions & an Agenda for ActionZoonoses & Emerging Diseases of the 21st CenturyWhat have we learned and how are we adapting? Avian Influenza FMD Monkeypox
A Time Line for Zoonoses & Epidemics of the 21st Century But do not forget Eastern Equine Encephalitis, Lassa, Ebola, Nipah, Hendra, and Rift Valley Fever! All of which threatened during the same time span.
Today we have“Microbial Club Med”(concept courtesy of Lonnie King) • 75% of emerging diseases are zoonotic • viruses most common • 60% of pathogens are zoonotic (Taylor et al., Proc. Roy. Soc. 2001) More than 99% of viruses remain to be discovered. Huge potential for future zoonotic emergence Daszak, 2003
A Time Line for Zoonoses & Epidemics of the 21st Century Risk assessment is a great approach, but preparedness is all important!
Society’s role in meeting the challenge of emerging diseases and zoonoses “I know of no safe depository of the ultimate posers of society but the people themselves, and if we think them not enlightened enough to exercise control with a wholesome discretion, the remedy is not to take it from them, but to inform their discretion.” Thomas Jefferson We must educate!